In the health care industry and, more specifically, in the field of nuclear medicine, radioactive materials known as radiopharmaceuticals are used in various applications, including non-invasive imaging of patients for various diagnostic, as well as therapeutic purposes. Over the years, the health care industry has developed many different radiopharmaceuticals designed to facilitate such applications.
Radiopharmaceuticals should be handled carefully because of their radioactive nature. Recognizing the need to carefully handle radioactive materials, various governmental agencies, including the U.S. Department of Transportation, the Nuclear Regulatory Commission (NRC), the Department of Transportation (DOT), and the Occupational Health and Safety Administration (OSHA), have promulgated regulations to ensure that they are handled safely. To avoid some of the overhead costs associated with addressing the above concerns, many hospitals have resorted to using outside pharmacy companies having expertise in the compounding and handling of radiopharmaceuticals to provide them with their radioactive drugs.
Typically, patients who require radioactive drugs require only a small dose of a specific drug. Therefore, if the number of patients generally requiring radioactive drugs is small, health care providers typically order radiopharmaceuticals in individual or “unit” doses for each specific patient. Furthermore, the radioactive agents in the drugs have various half lives and lose their effectiveness after a predetermined time period. Thus, if a hospital does not have the required demand, some of its unused radioactive agents may decay and become unusable. To avoid the expense of such in-house production of radioactive drugs, many hospitals now purchase each prescribed dose of a radioactive drug from an outside pharmacy.
The pharmacies which provide radioactive drugs to hospitals utilize the principles of mass production to reduce their per-unit costs. The pharmacies receive prescription orders and deliver the corresponding radioactive drugs to nearby hospitals. Each prescription is individually filled, and each dose of radioactive drug is packaged in a syringe intended for a specific patient. The syringes containing the radioactive drugs must be carefully handled and delivered inside containers offering some degree of radiation shielding. Furthermore, government regulations require syringes to be disposed of in a container that shields others from the risk of injury posed by their sharp hypodermic needles. Such a container, generally referred to as a “sharps” container, typically has an internal cavity or chamber that can hold at least one syringe. One type of sharps container has a chamber sealed by a spring-biased pivoting gate to keep syringes safely inside.
Conventionally, each dose of radioactive drug is packaged in a syringe intended for a specific patient, and transported and handled within a reusable apparatus having a radiation shield, commonly known as a radiopharmaceutical pig. The radiopharmaceutical pig typically is a two-part assembly, with an upper portion removably attached to the lower portion. Once the pig is assembled, it includes a sealed internal chamber suitable for carrying a syringe. The internal chamber of the radiopharmaceutical pig is surrounded by a radiation shield that is typically made of elemental lead. The heavy lead particles provide the desired radiation shielding. The radiation shield can be surrounded by an exterior shell, which typically is made of a polystyrene plastic. The exterior shell prevents damage to the radiopharmaceutical pig by absorbing any impact to it. By acting as a barrier between the radiation shield and the environment, the exterior shell also prevents lead particles from the radiation shield from contaminating the environment.
Once the syringe containing radioactive drugs is ready to be transported, it is placed into the internal chamber of the bottom portion of the radiopharmaceutical pig. The radiopharmaceutical pig is then assembled by removably attaching the top portion of the pig to the bottom portion of the pig. The assembled pig is then transported to the desired destination with the interior chamber containing the syringe and the radioactive drug.
Once the radiopharmaceutical pig containing the syringe and radioactive drug has arrived to its destination and the radioactive drug is ready to be used, the pig is disassembled and the syringe is removed. The dose is then injected into the patient, as needed. Once the syringe has been used, it is generally referred to as “spent,” but usually contains at least a small amount of residual radioactive drug. Additionally, the hypodermic needle of the spent syringe is now biologically contaminated from coming into contact with the patient. The contaminated spent syringe is then put back into the bottom portion of the radiopharmaceutical pig. The top portion of the radiopharmaceutical pig is then removably attached, usually by interlocking threads, to the bottom portion of the pig. Once the top and bottom portions of the radiopharmaceutical pig are removably attached to one another, the radiopharmaceutical pig is sent back to the pharmacy for proper disposal of the contaminated spent syringe.
Using the radiopharmaceutical pig apparatus and method described above has certain drawbacks. One such drawback is the additional expense and hazard that arises from contaminating the radiopharmaceutical pig. The spent syringe is often placed back into the radiopharmaceutical pigs with the needle uncapped. Therefore, any residual amount of radioactive drug or biologically contaminated blood can come into direct contact with the radiation shield of the pig and cause unsuspected contamination of the radiation shield. Consequently, subsequent doses of radiopharmaceuticals may be distributed in radiopharmaceutical pigs that are contaminated with biological and radioactive contaminants. Transporting radiopharmaceutical doses in contaminated pigs thus exposes both hospital staff and patients to potential environmental transmission of blood-borne pathogens, such as Human Immunodeficiency Virus (HIV), Hepatitis B Virus (HBV), and to harmful radioactive materials.
Additionally, because some of the materials used to make the radiation shield, including lead, are very porous, biological contaminants that contaminate the porous material can be very difficult to detect and remove. Often, biological contaminants cannot be detected in a radiation shield that is made of a porous material regardless of the detection methods used. Because biological contaminants often cannot be detected, any potential exposure to biological contaminants would require sterilization and sanitization of the radiation shield. Known processes of sterilizing and sanitizing the pig, including autoclaving, gas sterilization, high pressure steam, and moist heat treatment are often ineffective, time-consuming and expensive. Additionally, because known methods of sterilization and sanitation are often not effective at removing biological contaminants from the radiation shield, the contaminated radiopharmaceutical pig would have to be disposed of.
Radioactive materials can also be very difficult to remove from porous materials. Using known processes to try and remove radioactive contaminants and sanitize the pig is undesirable, because the various processes are often expensive, time-consuming and ineffective. Alternatively, disposing of the contaminated radiopharmaceutical pigs is also not a desirable option, because the radiopharmaceutical pigs are expensive to replace and difficult to dispose of if they contain hazardous materials such as lead.
Another drawback of the above method and apparatus is the exposure to potentially hazardous particles of the exposed radiation shield. The exposed radiation shield creates the potential danger that hazardous particles from the radiation shield will contaminate the environment or the user. Often, a radiopharmaceutical pig with a radiation shield made of lead will create lead dust particles that will remain in the radiopharmaceutical pig, or escape from the radiopharmaceutical pig, and settle on radiopharmacy surfaces. Accordingly, there is the potential danger of human inhalation or ingestion of lead dust from the lead radiation shield. Also, the lead particles could contaminate the syringe and radiopharmaceuticals inserted into the pig, and result in harmful lead particles being unknowingly injected into a patient. To avoid the potential that lead particles would contaminate the environment, the syringe or the radiopharmaceuticals, additional safety procedures and handling equipment that are time-consuming, expensive and not completely effective would need to be implemented. Additionally, if the radiopharmaceutical doses were contaminated with hazardous particles, they would be unuseable, and additional effort and expense would be required to obtain new doses and dispose of the contaminated ones.
The prior art attempted to solve some of the drawbacks described above. One approach involves using a disposable sharps container to encapsulate the syringe containing radiopharmaceuticals before inserting the syringe into the radiopharmaceutical pig. Typically, a disposable sharps container is a two-part assembly including a bottom portion, commonly called a housing, and a top portion, commonly called a cap. The sharps container can be assembled by removably attaching the cap and housing together to create a sealed internal chamber, sized to hold a syringe. In the approach used in the prior art, the sharps container acts as a barrier that prevents potentially hazardous particles from the radiation shield from contaminating the syringe or radiopharmaceuticals, and prevents biological and radioactive contaminants on the spent syringe from contaminating the radiation shield.
Once the syringe containing radiopharmaceuticals is ready to be transported, it is placed into the bottom portion, or housing, of the sharps container. The cap is then removably attached to the housing, thereby causing the syringe to be contained in the sealed internal chamber of the assembled sharps container. The sharps container and the syringe it contains are then inserted into the internal chamber of a radiopharmaceutical pig similar to the one described above. The radiopharmaceutical pig is then assembled and transported to the desired destination, where it is disassembled when the radiopharmaceutical is needed. Once the pig is disassembled, the cap of the disposable sharps container is removed from the housing, allowing the user access to the syringe. The syringe is then removed while the housing of the disposable sharps container remains in the lower portion of the radiopharmaceutical pig. The syringe is then used for its intended purpose and the contaminated spent syringe is placed back into the housing of the sharps container that remained in the lower portion of the pig. The cap of the sharps container is then placed back onto the housing of the sharps container, thereby encapsulating the contaminated spent syringe. The pig is then assembled with the sharps container and contaminated spent syringe inside the internal chamber of the pig. The assembled pig is then transported into the proper destination for disposal of the sharps container and contaminated spent syringe.
Alternatively, the method described above can be modified to transport the syringe containing radiopharmaceuticals without it being encapsulated in a sharps container. Instead, the sharps container is either included in the same shipping container as the assembled radiopharmaceutical pig or it is obtained through alternative means. Once the syringe has been used or spent it is placed into the bottom portion or housing of the sharps container and the cap is removably attached to the housing, encapsulating the syringe. The sharps container containing the spent syringe is then placed into the bottom portion of the radiopharmaceutical pig. The pig is then assembled and transported to the proper location for disposal of the sharps container and contaminated spent syringe. Using the radiopharmaceutical pig apparatus and methods described above also has certain drawbacks.
One such drawback is potential contamination that results if the user of the radiopharmaceutical pig does not use the disposable sharps container to contain the syringe either before or after its use. Often, users of the radiopharmaceutical pig forget to use the disposable sharps container. When the unused syringe is placed into the lower portion of the pig without the housing of the sharps container, hazardous particles from the radiation shield, like lead dust, can contaminate the syringe and the radiopharmaceuticals it contains. As mentioned above, the radiation shield is typically made of elemental lead, which is a hazardous material. Not using the disposable sharps container to contain the syringe before inserting it into the radiopharmaceutical pig creates the potential that the radiopharmaceutical doses are contaminated with hazardous particles. To avoid possible injury to patients or hospital staff, the radiopharmaceutical doses would need to be discarded and replaced with uncontaminated doses.
Another problem arises if the contaminated spent syringe is placed into the lower portion of the pig without the housing of the sharps container. The residual amount of radiopharmaceuticals and biological contaminants on the spent syringe would very likely come into direct contact with the radiation shield of the radiopharmaceutical pig, and would require expensive and time-consuming cleaning and sterilization of the radiation shield. Additionally, if the radiation shield could not be properly cleaned or sterilized, the contaminated radiopharmaceutical pig would need to be disposed of, resulting in additional expense. Therefore, the method and apparatus described in the prior art eventually results in contamination of the radiation shield of radiopharmaceutical pig, which can be difficult, to impossible, to clean, not to mention expensive and time-consuming.
Additionally, another drawback of the apparatus and method described above is the environmental contamination that can occur because the potentially hazardous particles from the radiation shield are exposed to the environment. When the pig is unassembled, the radiation shield and any loose particles of the radiation shield are exposed to the environment. Hazardous particles, such as lead dust, may escape from the inner chamber of the pig, contaminating the environment and exposing individuals in the vicinity to potentially serious harm. To try to minimize the potentially serious harm that would result from exposure to hazardous particles, such as lead dust, additional safety procedures and handling equipment that are time-consuming, expensive, and not completely effective would need to be implemented.
Accordingly, there exists a need for an improved radiopharmaceutical pig that prevents particles from the radiation shield from contaminating the syringe, the radiopharmaceuticals or the environment, and that prevents biological or radioactive contaminants from contaminating the radiation shield or the environment. The present invention fulfills this need.